The present disclosure relates generally to optical fiber adapters or couplings for holding optical fiber connectors in alignment. More specifically, the present disclosure relates to a hybrid optical fiber adapter for coupling standard sized and micro connectors.
Fiber optics have become the standard cabling medium used by data centers to meet the growing needs for data volume, transmission speeds, and low losses. An optical fiber connector is a mechanical device disposed at an end of an optical fiber, and acts as a connector of optical paths, for example when optical fibers are joined to each other. An optical fiber connector may be coupled with an adapter to connect an optical fiber cable to other optical fiber cables or devices. An adapter generally includes a housing, or portion of a housing, having at least one port which is configured to receive and hold a connector to facilitate the optical connection of one connector to another connector or other device. For example, an LC adapter is typically configured to receive one or more standard sized LC connectors.
Hybrid adapters are typically designed to couple together a plurality of different types of optical fiber connectors. For example, FIG. 1A shows one example of a hybrid adapter for SC/FC type connectors. The SC/FC hybrid adapter 100 is configured to be mounted on a mounting panel 102 using mounting screws 104. The SC/FC hybrid adapter 100 a first adapter end 106 configured to receive an SC connector 108, and a second adapter end 110 configured to receive an FC connector 112. The second adapter end 110 is configured to pass through an opening 114 of the mounting panel 102, allowing each of the SC and FC connectors to be received from opposite sides of the mounting panel. FIG. 1B shows the SC/FC hybrid adapter 100 of FIG. 1A, assembled to the mounting panel 102 and coupled to each of the SC and FC connectors 108 and 112.
One disadvantage of traditional hybrid adapters as shown in FIGS. 1A and 1B is that they are bulky, taking too much space on both sides of the adapter. Specifically, they are configured to couple to full size connectors, and thus the corresponding adapter ends are bulky. This is a drawback, for example, when one end of the adapter is intended to be disposed inside a small module, as both the corresponding adapter end and the connector will occupy too much space within the module. Therefore, in lieu of coupling to two full size connectors, some hybrid adapters have been designed to accommodate coupling a standard full size optical fiber connector with a simplified optical fiber connector. A simplified optical fiber connector is merely a ferrule that may or may not have a metallic flange assembled onto the ferrule and which is used to terminate the end of an optical fiber.
For example, U.S. Pat. No. 5,719,977 titled “Optical Connector with Immovable Ferrule” discloses an adapter configured to couple to a standard size connector at one end and a simplified optical fiber connector at the other end. However, a disadvantage of such a hybrid adapter is that the simplified connector is held rigidly inside the adapter. Unlike standard size optical fiber connectors which allow the ferrule to float and also include an extension spring that is pre-loaded behind the ferrule, a simplified optical fiber connector may not include a spring behind the ferrule. Thus, the ferrule will be held rigidly inside one end of the adapter. However, for best optical performance, both ferrules in a mated pair should be floating, and subject to spring pressures that push the end faces of a pair of mated ferrules together. For example, FIG. 2A shows a micro circuit board adapter comprising of a ferrule alignment body 200 disposed within a ferrule spring 202. The ferrule spring 202 is mounted on a circuit board 204 via soldering holes 206. The ferrule alignment body 200 is configured to receive micro connectors 208 at each end. FIG. 2B shows the assembled adapter coupled to two micro connectors, such that each micro connector is disposed between a respective end of the ferrule alignment body 200 and a respective end of the ferrule spring 202. However, the adapter of FIGS. 2A and 2B is not a hybrid adapter and is designed for mounting directly on a circuit board rather than coupling an external optical fiber connector to a connector disposed within a module.
Accordingly, there is a need for hybrid optical fiber adapters that occupy less space within a module than conventional hybrid adapters, while enabling better optical performance by providing spring pressure and allowing the ferrules to float.